Technical Field of the Invention
The present invention relates to an information code medium in which an information code, such as a bar code or a two-dimensional code, is recorded, and to an apparatus, a system and a method of reading an information code from the information code medium.
Related Art
Information codes, such as bar codes and two-dimensional codes, are widely used for various purposes. The ways of using such information codes are also various. For example, a patent document JP-A-2006-318010 discloses a technique for putting an information code on an article without raising any aesthetic or spatial problems. According to this technique, an invisible information medium layer configured by including a coating agent layer is arranged on an article. The coating agent layer is configured to emit light other than visible light (such as infrared light), when ultraviolet light beam is radiated thereto.
According to the technique disclosed in the patent document JP-A-2006-318010, the coating agent layer is also formed into the shape of the bar code or the two-dimensional bar code to be provided on an article. Therefore, normally, the portion that is the invisible information medium layer, in which the information code is arranged, is hardly visible. When an ultraviolet light beam is applied to this portion, the presence of the information code can be visually recognized through the detection of the infrared light emitted from the portion.
Such an information code can also be conveniently used for determining the authenticity of an article. For example, in practical management of articles, an authentic information code may be put on each of authentic articles. Then, in a distribution channel, stores or the like, a manager who manages articles may read the information code put on each of the articles to easily determine the authenticity of the articles. In this way, for example, inauthentic articles can be efficiently found or removed.
For example, when articles are practically managed in this way, a tag (e.g., price tag) may be fastened to each article using a cord, with an information code being printed on the tag. However, in this method, the authenticity of an article can no longer be determined after the tag has been removed. For example, a valuable article, such as a watch, may once be sold and then be resold. In this case, there is a problem that, since the information code is not directly put on the article to be resold, the authenticity of the article cannot be determined on the basis of the information code. However, not applying only to the case of reselling an article, if an information code for determining the authenticity of an article is directly put on the article, beauty of the appearance of the article may be damaged. In addition, since the presence of the information code on the article is easily recognized, there is a concern that this may lead to fraudulent use of the information code.
As a measure against such a problem, it is desirable that an information code is put on an article in such a way that the information code is invisible in a normal environment. A technique related to this measure is disclosed in the patent document JP-A-2006-318010 mentioned above. According to this technique, an invisible information medium layer including a coating agent layer is arranged on an article to be allocated with an information code. The coating agent layer is configured to emit light beam by being excited, that is, light other than visible light (such as infrared light), when an ultraviolet light beam is radiated thereto. The patent document also describes that the coating agent layer is formed into the shape of the bar code or the two-dimensional bar code. Thus, the portion in which an information code is located is provided as the invisible information medium layer which is hardly visible in a normal environment. When ultraviolet light is applied to this portion, the information code can be visually recognized by detecting the infrared light emitted from the portion.
However, in the configuration disclosed in the patent document JP-A-2006-318010, the coating agent layer has to be separately applied, for example, to the external surface of an article to which an information code is allocated. Accordingly, concavities and convexities are likely to be formed on the external surface of the article. In particular, when the coating agent layer is formed into the shape of the bar code or the two-dimensional bar code, complicated concavities and convexities are formed on the external surface of the article.
For example, such a concavo-convex appearance (e.g., in particular, the shadow of the concavities and convexities cast over the surface when they are seen from obliquely above) or a rough touch of the concavities and convexities is unlikely to meet the users' aesthetic preferences. Although the coating agent layer is configured as an invisible information medium layer, the concavities and convexities of the coating agent layer applied to the surface of the article allow the shape of the information code to be defined. If the shape of the information code cannot be defined, the concavities and convexities may imply the allocation of some information to the article and thus safety measures are not necessarily complete.